Cuprous complexes



' posed of acrylonitrile interpolymers are United States Patent 3,156,708 CUPROUS COMPLEXES Christian F. Horn, South Charleston, W. Va., assignor to Union Carbide Corporation, York No Drawing. Filed Dec. 27, 1960, Ser. No. 78,251 4 Claims. (Cl. 260-848) This invention relates to novel cuprous complexes. More particularly, this invention relates to novel, stable, epoxycyclohexanecarbonitrile cuprous complexes useful in aiding the dyeing of acrylonitrile fibers.

It is known in the textile field that synthetic fibers comextremely diflicult to d-ye; To overcome this difficulty, a copper dyeing method was proposed wherein dyeing occurred in the presence of cuprous ions. Satisfactory dyeing results are obtained using the above described process; however, there are some characteristics of this process which make it less desirable when used in large scale dyeing. When the cuprous ion is produced in the dye bath by the reaction of copper compounds such as, copper sulfate, and reducing agents, several deficiencies arise. These deficiencies center around the reduction of the cupric ion to the active cuprous ion. If the rate of reduction is not carefully controlled, two undesirable occurrences may result. Initially, if the cupric ion is not fully reduced, the chemicals in the bath will be unsatisfactory for use in the dyeing process. On the other hand, if the cupric ion is. over-reduced, metallic copper may be present in the bath which will impair both light stability and the color shade of the fiber. In addition, the above described problemsmake the dyeing formulations extremely diflicult to reproduce; It is the combination of these problems which have discouraged the use of the cuprous-ion technique. There has therefore been a long felt need in the art for a stable cuprous-i on complex which could be added directly to the dyebath without going through the reduction process.

I have discovered a class of novel, inorganic acid salts of cuprous complexes of epoxycyclohexanecarbonitrile which are stable and which can be used to provide outstanding results in the cuprous-ion dyeing technique. A distinct advantage of the compounds of this invention pertains to the fact thatnot only are the cuprous complexes of epoxycyclohexanecarbonitrile a dyeing aid in acid dyes but also inthe dyeingprocess, the epoxycyclohexanecarbonitrile molecules act as dye carriers. Thus very deep color shades of the dyed fabric can be obtained in the use of the compounds of this invention without the addition of conventional dye carriers.

The epoxyclohexanecarbonitrile portion of these complexes can be represented by the general formula:

wherein each R, individually, represents a hydrogen atom or an alkyl radical, preferably containing from 1 to 6 carbon atoms.

The epoxyclohexanecarbonitriles which are used to prepare the novel cuprous complexes of this invention include for example: 3,4-epoxycyclohexanecarbonitrile, 2,3-epoxycyclohexanecarbonitrile, 1,2-epoxycyclohexanecarbonitrile, 2-methyl-3,4 epoxycyclohexanecarbonitrile, 3ethyl-3,4-epoxycyclohexanecarbonitrile, S-n-hexyl 3,4- epoxycyclohexanecarbonitrile, 2-isopropyl 2,3 epoxycyclohexanecarbonitrile, 5-ethyl-2,3 epoxycyclohexanecarbonitrile, 4-n-hexyl-2,3 epoxycyclohexanecarbonitrile, 3-

a corporation of New bond of the cyclohexenecarbonitrile. 'peracid consumed during the epoxidation reaction can 3,155,708 Patented Nov. 10, 1964 ice isopropyl-1,2-epoxycyclohexanecarbonitrile, S-n-hexyl-l, 2'-epoxycyclohexanecarbonitrile, and the like.

' The cuprous salts which are preferably used in the production of the cuprous complexes of this invention include the cuprous salts such as, for example, cuprous chloride, cuprous bromide, cuprous iodide, cuprous nitrate, cuprous sulfate, cuprous phosphate, and the like.

The novel cuprous complexes of epoxycyclohexanecarbonitrile can be readily produced by reacting the cuprous salts such as, for example, cuprous chloride, with an epoxycyclohexanecarbonitrile such as, for example, 3,4- epoxycyclohexanecarbonitrile at a temperature of from about 20 C. to about 100 C. for a period of time sufficient for the cuprous complex to form and dissolve in the reactant solution. The reaction can be conducted in an inert organic reaction medium which has a function of a solvent in the event that the epoxycyclohexanecarbonitrile starting material is a solid at room temperature. The time of reaction can range from a few minutes to as long; as 24 hours depending on the reaction temperature and the specific reactants used. In general, when the cuprous salts are added to the epoxycyclohexanecarbonitrile to produce the products of this invention, the resulting' reaction is exothermic. The temperature is controlled to maintain the preferable temperature of from about 40 C. to about C. After the initial exothermic reaction has run its course, additional heat can be applied to maintain the temperature range and complete the reaction more rapidly. V I

In producing the novel cuprous complexes of epoxycyclohexanecarbonitrile, the epoxycyclohexanecarbonitrile is preferably employed in mole ratios greater than the equivalent amount of cuprous salt present. The preferred range is from about a 1:1 to 1:4 mole ratio of cuprous salts to epoxycyclohexanecarbonitrile. Higher or lower ratios are operable; however, a high excess of epoxycyclohexanecarbonitrile is not economically feasible and lower ratios do not make full use of the cuprous salts charged.

The epoxycyclohexanecarbonitriles can be readily preparedby the reaction of a cyclohexenecarbonitrile such as 3-cyclohexenecarbonitrile, with a peracid, e.g. perbenzoic acid, perpropionic acid, peracetic acid, and the like, preferably in an inert normallydiquid organic medium such as ethyl acetate, acetone, butyl acetate, and the like, at a temperature in the range of from about 0 C. to about C., preferably from about 25 C. to about 80 C., for a period of time sufficient to introduce oxirane oxygen at the site of the carbon to carbon double The quantity of be readily determined during the course of the reaction by well-known procedures. A residence time of from about several minutes to about several hours, e.g., 30 minutes to 18 hours, is satisfactory in many instances. Theoretically, to effect substantially complete epoxidation of. the cyclohexenecarbonitrile at least a stoichiometric quantity of peracid per carbon to carbon double bond of the cyclohexenecarbonitrile should be employed. The inert normally liquid organic vehicle and acid byproduct can be recovered from the reaction product mixture for example, by distillation under reduced pressure. If desired, the residue product can be subjected to fractional distillation, crystallization, and the like, to obtain the epoxycyclohexanecarbonitrile in high purity.

In producing the novel cuprous complexes of this invention, it is desirable, although not necessary, to conduct the reaction in an atmosphere of an inert gas free of elemental oxygen, such as an atmosphere of nitrogen carbon dioxide, helium, and the like. The inert atmosphere aids in decreasing the possible air oxidation of the cuprous salts to the undesirable cupric salts although the cuprous complexes of epoxycyclohexanecarbonitrile can be produced in the presence of air.

Among the cuprous complexes of this invention which can be produced by the above described process are, for

example: complex of cuprous chloride and 3,4-epoxycyclohexanecarbonitrile, complex of cuprous chloride and 1,2 epoxycyclohexanecarbonitrile, complex of cuprous chloride and 2-methyl-3,4-epoxycyclohexanecarbonitrile, complex of cuprous chloride and 3-ethyl-3,4-epoxycyclohexanecarbonitrile, complex of cuprous bromide and -nhexyl-3,4-epoxycyclohexanecarbonitrile, complex of cuprous bromide and 2-isopropyl-2,3-epoxycyclohexanecarbonitrile, complex of cuprous nitrate and 5-ethy1-2,3- epoxycyclohexanecarbonitrile, complex of cuprous nitrate and 4-n-hexyl-2,3-epoxycyclohexanecarbonitrile complex of cuprous sulfate and 3-isopropyl-1,2- epoxycyclohexanecarbonitrile and the like.

The cuprous complexes of the invention can be recovered from their reaction mixtures in high purity by cooling the reaction mixture to precipitate the cuprous complex and isolation by conventional filtration procedure. If the cuprous complex reaction product does not crystallize on cooling, the reaction product can be precipitated by the addition of an organic non-solvent such as acetone, ethyl ether, ethyl acetate, dioxane, and the like. If additional purification of the copper complexes is desired, conventional recrystallization procedures can be used.

The following examples are illustrative:

Example 1 Cuprous chloride grams) was added portionwise with agitation to 61.5 grams of 3,4-epoxycyclohexanecarbonitrile in a nitrogen atmosphere. The reaction was exothermic, raising the temperature from about 40 C. to 55 C. during the addition. On completion of the addition of the cuprous chloride, a thick paste-like precipitate was formed preventing stirring. The reaction mixture was heated to 80 C. for 2 hours, then cooled to room temperature and filtered. The filtered product was washed with acetone, dried at room temperature and analyzed to be the desired cuprous chloride complex of 3,4-epoxycyclohexanecarbonitrile. It melted at 170 C.- 175 C.

The infrared spectrum and analytical data confirmed the structure as the complex of cuprous chloride and 3,4- epoxycyclohexanecarbonitrile.

In an analogous manner, 2,3-epoxycyclohexanecarbonitrile is reacted with cuprous nitrate to obtain the corresponding cuprous nitrate complex of 2,3-epoxycyclohexanecarbonitrile. Additionally, 5-n-hexyl-3,4-epoxycyclohexanecarbonitrile is reacted with cuprous sulfate to obtain the corresponding cuprous sulfate complex of 5-nhexyl-epoxycyclohexanecarbonitrile.

Example 2 A 5 gram sample of scoured and dried knitted tubing of continuous yarns composed of a terpolymer of acrylonitrile, vinyl chloride and vinylidene chloride [in a ratio, respectively, of 70:20:10] was added to a 200 milliliter total volume aqueous dyebath containing 1 percent by weight of the yarn of Pergegal OK (a cationic condensation product of ethylene oxide and an organic amine marketed by General Aniline and Film Corporation) 2 percent by weight of the yarn of concentrated sulfuric acid, 3 percent by weight of the yarn of Xylene Milling Blue G.L. (Acid Blue 102-50320) and 5.0 percent by weight of the yarn of the cuprous chloride complex of 3,4-epoxycyclohexanecarbonitrile. The cuprous chloride complex of 3,4-epoxycyclohexanecarbonitrile was added as a mixture of 5 parts by weight of acetonitrile to 1 part by weight of cuprous chloride complex of 3,4-epoxycyclohexanecarbonitrile. The bath temperature was raised to boiling in about 20 minutes and held for 90 minutes at the boiling temperature. The dyed fabric was then raised, scoured, rinsed, hydroextracted and dried at 130 C. for 10 minutes. After drying, the dyed fabric had a final K/S value of 15.7. The common Fade-O-Meter test indicated a light fastness rating of the dyed fabric of 40 hours.

. What is claimed is:

1. The cuprous complex produced by the reaction of a cuprous salt of an inorganic mineral acid With an epoxycyclohexanecarbonitrile of the formula:

wherein each R, individually, is selected from the group consisting of hydrogen and alkyl of from 1 to 6,carbon atoms, at 100 C.

2. The cuprous complex produced by the reaction .of

a temperature of from about 20 C. to about cuprous chloride with 3,4-epoxycyclohexanecarbonitrile of 20 is approximately twice as deep as a K/S the K/S values is set forth by D. B. Judd, Color in Business, Science and Industry, 1952,

References Cited in the file of this patent UNITED STATES PATENTS 2,894,959 Phillips et al. July 14, 1959 2,911,425 Scalera et al. Nov. 3, 1959 3,042,695 Horn July 3, 1962 3,051,736 Horn Aug. 28, 1962 OTHER REFERENCES Mousseron et al.:

Chem. Abstract., vol. 42, col. 491g (1948).

Mousseron et al.: (1951).

Chem. Abstract., vol. 45, col. 1967e 

1. THE CUPROUS COMPLEX PRODUCED BY THE REACTION OF A CURPOUS SALT OF AN INORGANIC MINERAL ACID WITH AN EPOXYCYCLOHEXANECARBONITRILE OF THE FORMULA: 